Improve Git Credential Helper Detection for Linux (GCM & libsecret support) (#3264)

* feat: add support for Git Credential Manager (GCM)

- Update GIT_CREDENTIAL_REGEX to match git-credential-manager
- Add tests to verify GCM is recognized and handled

Ref: https://git-scm.com/doc/credential-helpers

* feat: support for git-credential-libsecret in credential helper detection

- Extend GIT_CREDENTIAL_REGEX to recognize git-credential-libsecret, enabling integration with Secret Service-compatible keyrings (e.g., GNOME Keyring, KDE Wallet) on Linux.

- Add unit tests to validate detection and handling of git-credential-libsecret

Ref: https://git-scm.com/doc/credential-helpers

---------

Co-authored-by: Lucain <[email protected]>

Author: danchev

src/huggingface_hub/utils/_git_credential.py

@@ -27,7 +27,7 @@
         ^\s* # start of line
         credential\.helper # credential.helper value
         \s*=\s* # separator
-        (\w+) # the helper name (group 1)
+        ([\w\-\/]+) # the helper name or absolute path (group 1)
         (\s|$) # whitespace or end of line
     """,
     flags=re.MULTILINE | re.IGNORECASE | re.VERBOSE,

tests/test_utils_git_credentials.py

@@ -18,6 +18,8 @@
 [credential]
     helper = store
     helper = cache --timeout 30000
+    helper = git-credential-manager
+    helper = /usr/libexec/git-core/git-credential-libsecret
 """
 
 
@@ -38,6 +40,8 @@ def test_list_credential_helpers(self) -> None:
         helpers = list_credential_helpers(folder=self.cache_dir)
         self.assertIn("cache", helpers)
         self.assertIn("store", helpers)
+        self.assertIn("git-credential-manager", helpers)
+        self.assertIn("/usr/libexec/git-core/git-credential-libsecret", helpers)
 
     def test_set_and_unset_git_credential(self) -> None:
         username = "hf_test_user_" + str(round(time.time()))  # make username unique